hi
this problem is for disable rest api.
you just:
1- go to setting item and select (disable rest api settings)
2- check mark this items:
contact-form-7/v1
/contact-form-7/v1/contact-forms
/contact-form-7/v1/contact-forms/(?P<id>\d+)
/contact-form-7/v1/contact-forms/(?P<id>\d+)/feedback
/contact-form-7/v1/contact-forms/(?P<id>\d+)/refill
3-save this settings
now you can sent form with contact form7 without loggin
